Re: [PATCH v2 1/2] mm/rmap: rename page__anon_vma to page_anon_vma for consistency

[David Hildenbrand <david@redhat.com>]

On 18.04.25 12:50, Lorenzo Stoakes wrote:
> On Fri, Apr 18, 2025 at 12:40:10PM +0200, David Hildenbrand wrote:
>> On 18.04.25 11:55, Ye Liu wrote:
>>> From: Ye Liu <liuye@kylinos.cn>
>>>
>>> Renamed local variable page__anon_vma in page_address_in_vma() to
>>> page_anon_vma. The previous naming convention of using double underscores
>>> (__) is unnecessary and inconsistent with typical kernel style, which uses
>>> single underscores to denote local variables. Also updated comments to
>>> reflect the new variable name.
>>>
>>> Functionality unchanged.
>>>
>>> Signed-off-by: Ye Liu <liuye@kylinos.cn>
>>> ---
>>>    mm/rmap.c | 8 ++++----
>>>    1 file changed, 4 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/mm/rmap.c b/mm/rmap.c
>>> index 67bb273dfb80..b509c226e50d 100644
>>> --- a/mm/rmap.c
>>> +++ b/mm/rmap.c
>>> @@ -789,13 +789,13 @@ unsigned long page_address_in_vma(const struct folio *folio,
>>>    		const struct page *page, const struct vm_area_struct *vma)
>>>    {
>>>    	if (folio_test_anon(folio)) {
>>> -		struct anon_vma *page__anon_vma = folio_anon_vma(folio);
>>> +		struct anon_vma *page_anon_vma = folio_anon_vma(folio);
>>
>> I'm extremely confused why this should not simply be called "anon_vma". Why
>> do we need the "page" in here *at all* ?
> 
> Presumably to differentiate from the VMA's anon_vma, but it seems redundant
> and silly to preface it as the page's (really, folio's) anon_vma.

Exactly, thus my confusion :)

> 
> The original patch is strictly an improvement so I'm fine with that, but we
> could also rename this to anon_vma to make the function a little simpler to
> read.
> 
> I guess the key bit where this becomes vaguely relevant is:
> 
> 		    vma->anon_vma->root != page_anon_vma->root
> 
> This whole thing seems to be to deal with races with unuse_vma() as per the
> comment.
> 
> Anyway, TL;DR: fine with that rename if we want it!

Okay, let's drop the "page_" part if possible.

-- 
Cheers,

David / dhildenb